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The dilution enthalpies of four 2′-deoxynucleosides, namely 2′-deoxyuridine (dU), 2′-deoxycytidine (dC), 2′-deoxyguanosine (dG) and 2′-deoxythymidine (dT), in (dimethylsulfoxide (DMSO) + water) mixtures of various mass fractions (wDMSO = 0 to 0.30) have been determined at T = 298.15 K, respectively, using an isothermal titration calorimeter (ITC200 MicroCal). On the basis of McMillan–Mayer’ theory, enthalpic pair wise self-interaction coefficients (hxx) of each compound at different values of wDMSO have been evaluated from successive dilution enthalpies. It was found that the values of hxx are all large negative and increase gradually with wDMSO across the whole composition range of the mixed solvent studied, though the degree of variation among them is somewhat different. The results indicate that (hydrophilic + hydrophilic) interactions are prevailing over (hydrophobic + hydrophobic) and (hydrophobic + hydrophilic) interactions in the ternary aqueous solutions under study.

The dilution enthalpies of nicotinamide (NA) and isonicotinamide (INA) in (dimethyl sulfoxide (DMSO) + water) and (dimethylformamide (DMF) + water) mixed solvents (M1 and M2) at 298.15 K have been determined, respectively, using an isothermal titration calorimeter (MicroCal ITC200). On the basis of the McMillan-Mayer theory, enthalpic pairwise self-interaction coefficients (hxx) of NA and INA in both M1 and M2 aqueous mixed solvents (mole fractions of cosolvents xcos = 0 to 0.10) have been calculated. It was found that the values of hxx are all large negative, with the relative magnitudes hxx(NA) hxx (in M2) for both NA and INA, and that all of them increase monotonously with the concentrations of cosolvents (both DMF and DMSO). It implies that an intense exothermic effect accompanies with the pairwise hydrophilic–hydrophilic self-interactions, in which the meso-isomer (NA) behaves as a stronger molecular associator than the para-isomer (INA).

Dilution enthalpies of two pairs of α-amino acid enantiomers, namely l -proline vs d -proline, and l -hydroxyproline vs d -hydroxyproline, in water-rich regions of dimethyl formamide (DMF) + H2O and dimethylsulfoxide (DMSO) + H2O mixtures (mass fractions of cosolvents wCOS = 0 to 0.30) have been determined respectively at 298.15 K by isothermal titration calorimetry (ITC). The successive values of dilution enthalpy obtained in a single run of ITC determination were used to calculate homochiral enthalpic pairwise interaction coefficients (hxx) at the corresponding composition of mixed solvents according to the McMillan–Mayer’ statistical thermodynamic approach. The sign and magnitude of hxx were interpreted in terms of solute–solute interactions mediated by solvent and cosolvent molecules, and preferential configurations of homochiral pairwise interactions ( l – l or d – d pairs) in aqueous solutions. The variations of hxx with wCOS were considered to be dependent greatly on the competition equilibrium between hydrophobic and hydrophilic interactions, as well as the structural alteration of water caused by the two highly polar aprotic cosolvents (DMF and DMSO). Especially, it was found that when one of the two kinds of interactions (hydrophobic or hydrophilic interactions) preponderates over the other in solutions, enthalpic effect of homochiral pairwise interactions is always remarkable, and is characterized by a large absolute value of hxx, positive or negative, which corresponds respectively to the prevailing interactions of hydrophobicity or hydrophilicity. Interestingly, it was also found that the hxx values of l -enantiomers are generally larger than those of d -enantiomers across the whole studied composition range of mixed solvents, i.e. |hLL| > |hDD|, which is defined as enthalpic discrimination effect and attributed to the influence of preferential configuration on homochiral pairwise interactions in aqueous solutions.

Dilution enthalpies of two penicillamine enantiomers, namely, d-penicillamine, l-penicillamine, and their racemate d,l-penicillamine, in N,N-dimethylformamide (DMF) + water mixtures of various compositions have been determined at 298.15 K respectively, using an isothermal titration calorimeter (MicroCal ITC200). According to the McMillan–Mayer theory, homochiral enthalpic pairwise interaction coefficients (hXX) of the three penicillamines in DMF + water mixtures of different mass fractions (wDMF = 0 to 0.3) have been calculated regressively. It is found that hXX coefficients of each enantiomer and their racemate change increasingly with wDMF to the maxima at wDMF = 0.20 and then decrease relatively rapidly, which follows the order hLL > hDD ≈ hRR > 0 (R represents the racemate mixture of penicillamine). The results are discussed from the point of view of competitive equilibrium between hydrophobic and hydrophilic interactions in solutions.

The dilution enthalpies of four 2′-deoxynucleosides, namely 2′-deoxyuridine (dU), 2′-deoxycytidine (dC), 2′-deoxyguanosine (dG) and 2′-deoxythymidine (dT), in dimethylformamide (DMF) + water mixtures have been determined at 298.15 K respectively, using an isothermal titration calorimeter (ITC200 MicroCal). On the basis of the McMillan–Mayer theory, the homotactic enthalpic pairwise interaction coefficients ( h XX ) of the four 2′-deoxynucleosides in DMF + water mixtures of various mass fractions ( w DMF = 0–0.30) have been calculated. It was found that the values of h XX of the four 2′-deoxynucleosides are all large negative and increase gradually across the whole studied composition range of the mixed solvent, though the variation degrees of them are somewhat different. The results are discussed from the point of view of solute–solute and solute–solvent interactions in solutions.

This study presented Computational Fluid Dynamic (CFD) analysis of the effect of co-firing coal blended with biomass, which is saw dust here. This complex problem which is because of its turbulent on the chemical reactions has been simulated in this paper for the purpose to decline the large amount of cost of doing experiment. The CFD analysis includes the prediction of vectors of the gas phase and DPM burnout result alike. What’s more, the reduction of CO2 by coal blended with different proportions of biomass has been presented because of low content of char in biomass. The mathematical models consist of models for turbulence flow(RNG K-EPSILON MODEL);non-premixed model with two mixture fractions/PDF model; and radiation (P-1 radiation model). The coal is from An Qin in China, and then respectively blended with 5% and 10% saw dust for co-combustion.